This thesis is concerned with the development of a computational model and simulation technique capable of capturing the complex physics behind the intriguing phenomena of Elasto-capillarity. Elastocapillarity refers to the ability of capillary forces or surface tensions to deform elastic solids through a complex interplay between the energy of the surfaces (interfaces) and the elastic strain energy in the solid bulk. The described configuration gives rise to a three-phase system featurin...

Eukaryotic cells determine their shape and organize their interior through a dynamic actin cytoskeleton that forms a variety of architectures, each crucial for a unique cellular function. Common to all actin structures is their growth from soluble subunits that assemble into filaments. The assembly of functional actin networks requires control over the speed at which filaments grow. How this can be realized at the high but variable concentrations of soluble actin subunits found in cells is no...

Bei der Planung von neuen Windenergieanlagen ist das Landschaftsbild ein häufiger Diskussionspunkt in der Abwägung. Für dessen Bewertung gibt es kein einheitliches Verfahren, das war der Anlass bereits existierende Landschaftskategorisierungssysteme daraufhin zu untersuchen, ob man sie für eine Abschätzung der Bewertungsänderungen durch Windenergieanlagen nutzen kann. Die Datengrundlage stammt aus einer Online-Befragung mit über 800 teilnehmenden Personen, die ihre Wahrnehmungen zu über 200 ...

Kritische Infrastrukturen (KRITIS) sind komplexe, hochgradig vernetzte Systeme, die aufgrund der von ihnen erbrachten Versorgungsleistungen von unerlässlicher, ‚kritischer‘ Relevanz für moderne Gesellschaften sind. Gemäß § 2 Abs. 2 Nr. 3 Satz 4 des Raumordnungsgesetzes (ROG) ist „[d]em Schutz kritischer Infrastrukturen [..] Rechnung zu tragen“, was KRITIS in ihrem funktionalen, grenz- und systemüberschreitenden Charakter zu einer Aufgabe der Raumordnung macht. Diese Dissertation schafft eine...

This contribution presents a theoretical and computational framework for two-scale shape optimisation of nonlinear elastic structures. Particularly, minimum compliance optimisation problems with composite (matrix-inclusion) microstructures subjected to static loads and volume-type design constraints are focused. A homogenisation-based FE2 scheme is extended by an enhanced formulation of variational (shape) sensitivity analysis based on Noll’s intrinsic, frame-free formulation of continuum mec...

A gradient-enhanced ductile damage model at finite strains is presented, and its parameters are identified so as to match the behaviour of DP800. Within the micromorphic framework, a multi-surface model coupling isotropic Lemaitre-type damage to von Mises plasticity with nonlinear isotropic hardening is developed. In analogy to the effective stress entering the yield criterion, an effective damage driving force—increasing with increasing plastic strains—entering the damage dissipation potenti...

Rotating packed beds (RPBs) overcome gravitational limitations as found in distillation or absorption columns by means of centrifugal force. The concept enables an intensified mass and heat transfer that leads to lower equipment volumes or increased performance. To impose centrifugal forces on gases or liquids the RPB consist of a motor-driven and packing equipped rotor in a static casing. An additional degree of freedom is offered due to the dependency of mass transfer performance ...

Classification and semantic instance segmentation applications are rarely considered for automotive radar sensors. In current implementations, objects have to be tracked over time before some semantic information can be extracted. In this thesis, data from a network of 77 GHz automotive radar sensors is used to construct, train and evaluate machine learning algorithms for the classification of moving road users. The classification step is deliberately performed early in the process chain ...

Due to the advancing energy system transformation and the increasingly complex and dynamic environment in which factories have to operate, the energy efficiency and flexible design of production systems are becoming more important. Since the use of automated guided vehicles is a promising approach to enhance the flexibility of intralogistics, their electrical power requirements are analyzed. Based on the measurement data obtained, different movement modules of an automated guided vehicle are ...

The goal of this work is to investigate the use of exciton polariton vortices for all optical information processing. To achieve this goal, we develop a novel technique based on sorting orbital angular momentum states of light, which allows for detecting and temporally tracing vortices in a light beam. We successfully implement and benchmark this technique and apply it to demonstrate the spontaneous formation of exciton polariton vortices inside all optically excited annular trapping potentia...

Column-beam joints are one of the most critical zones of concrete structures, especially under unpredicted heavy loads and lateral loads such as seismic. Failure of the joints can even lead to failure of structures in their entirety. The low strength capacity of concrete is a reason of sensitivity of the region. Shape memory alloy (SMA) plates can be employed in order to overcome this weakness and increase the stiffness of joints in existing structures. SMA is a smart material whose functiona...

Microtubules are hollow cylindrical filaments that are part of the cytoskeleton. During their growth, they exhibit “dynamic instability”, i.e., they can suddenly switch from growing to shrinking (catastrophe) and vice versa (rescue). Obtaining a microscopic understanding of this dynamic instability will also provide a better insight into basic cell functions like cell division and can provide a pathway to manipulate such processes. We introduce and parameterize a microtubule model that combi...

With high certainty, extreme weather events will intensify in their impact within the next 10 years due to climate change-induced increases in hazard probability of occurrence and simultaneous increases in socio-economic vulnerability. Data from previous mega-disasters show that losses from disruptions of critical services surpass the value of direct damages in the exposed areas because critical infrastructures [CI] are increasingly (inter-) dependent. Local events may have global impacts. Sy...

Selective laser melting (SLM) has gained large interest due to advanced manufacturing possibilities. However, the growing potential also necessitates reliable predictions of structures in particular regarding their long-term behaviour. The constitutive and structural response is thereby challenging to reproduce, due to the complex material behaviour. This motivates the aims of this contribution: To establish a material model that accounts for the behaviour of the different phases occurring du...

The possibility of accurately identifying thermal material parameters on the basis of a simple tension test is presented, using a parameter identification framework for thermo-mechanically coupled material models on the basis of full field displacement and temperature field measurements. Main objective is to show the impact of the material model formulation on the results of such an identification with respect to accuracy and uniqueness of the result. To do so, and as a proof of concept, the ...

In the present work a novel process for energy generation from natural gas without concomitant CO2 emissions, namely the Bromination-Oxidation (BrOx) cycle, is proposed and studied. This process consists of two exothermic reactions and an internal brominere cycle. Methane and bromine react in the first reaction step to yield solid carbon, that is separated by means of a cyclone or a filter, and hydrogen bromide. The latter is oxidised with oxygen in a second reactor yielding water and bromine...